Amazon Redshift RA3 with managed storage is the the latest generation node type and allows you to scale compute and storage independently. Today, we’re announcing RA3.xlplus – the third and smallest member of the RA3 node-family. RA3 allows you to size your cluster based primarily on your compute needs. With the introduction of RA3.xlplus, you now have even more compute sizing options to choose from to address a broader set of workload requirements.
Source:: Amazon AWS